Such devices preferably serve to pass a lead and/or a lead-through (lead-through in the following description) while protecting it from moisture and contamination through an open space existing between the vehicle parts, where moisture and contamination impinge on said open space. These devices each have a fixing device for being arranged on the respective vehicle part and a bellows (sealing bellows) or the like between the fixing devices. Said bellows (sealing bellows) enables a relative movement between the fixing devices and/or the vehicle parts. Usually, the fixing devices are molded on the sealing bellows and are provided with a conical catch extension, a lip seal and an annular groove designed between the conical catch extension and the lip seal for being fixed tightly against the opening in the respective vehicle part wall. The respective fixing device can be additionally provided with a catch frame using which the fixing device can be tightly fixed against the edge surrounding the opening in the respective vehicle part wall. The catch frame serves to facilitate the assembly and to ensure a reliable fixation, particularly in a narrow installation space. In order to enable a relative movement by changing the distance between the vehicle parts, the sealing grommets must be flexible and must be dimensioned appropriately. Furthermore, they require an installation space in which they can assume a rest position in the smallest distance between the vehicle parts, out of which they can follow an increase in the distance. Examples of sealing grommets can be found in the patent applications DE 200 22 922 U1, DE 33 40 664 A1 and DE 101 01 014 A1.